Dot Net Code Snippets

Hi , we have to discuss about how to download a file from the database , we generally upload a file to database in binary form so how to download that file that is going to see here..

suppose if i upload a file and bind the file detail in Gridview or datalist there i have give the Download link - here i am passing the id of the specific row so using this is i will retrieve the file.
so we pass the id to other page to make the file as download.

 If Not Request.QueryString("id") Is Nothing Then
Dim As New SqlCommand("Select * from where download_id like @id", con)
Dim ID As New SqlParameter("@ID", SqlDbType.SmallInt, 2)
ID.Value = Request.QueryString("id")
ID.Direction = ParameterDirection.Input
cmd.Parameters.Add(ID)
cmd.Connection = con
con.Open()
Dim dRE As SqlDataReader
dRE = cmd.ExecuteReader()
While dRE.Read()
Dim myTitle As String = dRE.GetString(4).ToString 'document title
Dim myType As String = dRE.GetValue(5).ToString 'document type
If myTitle = "None" Or myType = "None" Then
message.Text = "No Attachements Present !"
Exit Sub
Else
Dim myDoc = dRE.GetSqlBinary(3) 'document


Response.Buffer = True
Response.Clear()
Response.AddHeader("content-disposition", "attachment; filename=" & myTitle)
'application/octet-stream
Select Case myType.ToLower
Case "doc"
Response.ContentType = "application/msword"
Case "docx"
Response.ContentType = "application/msword"
Case "ppt"
Response.ContentType = "application/vnd.ms-powerpoint"
Case "xls"
Response.ContentType = "application/x-msexcel"
Case "htm"
Response.ContentType = "text/HTML"
Case "html"
Response.ContentType = "text/HTML"
Case "jpg"
Response.ContentType = "image/JPEG"
Case "gif"
Response.ContentType = "image/GIF"
Case "pdf"
Response.ContentType = "application/pdf"
Case Else
Response.ContentType = "text/plain"
End Select
Response.BinaryWrite(myDoc.Value)
Response.Flush()
Response.Close()
If myDoc.isNull Then
message.Text &= "Retrieving File: " _
& myTitle & "." & myType & " Size: NULL
"
Else
message.Text &= "Retrieving File: " _
& myTitle & "." & myType & " Size: " & myDoc.ToString() & "
"
End If
End If
End While
con.Dispose()
con = Nothing
cmdDownloadDoc.Dispose()
cmdDownloadDoc = Nothing

End If
End Sub

We discuss about how to get the co-ordinates of the image , while you click on the image at runtime
so using javascript we will get the x and y co-ordinates of the image
so using this we can wirte the text on that image ie: where we clicked on that image.

Already i have posted the article how to write text on image check the GDI Labels

Javascript

<script language="JavaScript">
function point_it(event){

var txtX=document.getElementById('<%= XTextBox.ClientID %>');
var txtY=document.getElementById('<%= YTextBox.ClientID %>');
pos_x = event.offsetX?(event.offsetX):event.pageX-document.getElementById("pointer_div").offsetLeft;
alert(pos_x);


pos_y = event.offsetY?(event.offsetY):event.pageY-document.getElementById("pointer_div").offsetTop;
alert(pos_y);
txtX.value=pos_x;
txtY.value=pos_y;

}
</script&gt;

Here we have to discuss about how to create small rectangle with fill color and write text on image
for that you have to use some namespace

Imports System.IO
Imports System.Drawing
Imports System.Drawing.Imaging
Imports System.Drawing.Text
Imports System.Drawing.Drawing2D

// Code behind file is

Protected Sub Button3_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button3.Click
Response.Clear() ' make sure Nothing has gone to the client
Dim imgOutput As New Bitmap(120, 30, PixelFormat.Format24bppRgb) ' create a New 24bit, 120x30 pixel image
Dim g As Graphics = Graphics.FromImage(imgOutput) ' create a New graphic object from the above bmp
' Application("intPageCount") += 1 ' really dumb page counter

g.Clear(Color.DarkGreen) ' blank the image
g.SmoothingMode = SmoothingMode.HighQuality ' antialias objects
' draw the number on the image canvas in verdana 10pt font bold
'g.DrawString("Count: " & Application("intPageCount"), New Font("verdana", 14, FontStyle.Bold), SystemBrushes.WindowText, New PointF(2, 2))
g.DrawString("A 2", New Font("verdana", 14, FontStyle.Bold), SystemBrushes.WindowText, New PointF(6, 6))
' draw a graduated fill across the image
g.FillRectangle(New LinearGradientBrush(New Point(0, 0), New Point(200, 200), Color.FromArgb(0, 0, 0, 0), Color.FromArgb(255, 255, 255, 255)), 0, 0, 120, 120)
imgOutput.Save(Response.OutputStream, ImageFormat.Jpeg) ' output to the user
' tidy up
g.Dispose()
imgOutput.Dispose()
Response.End()
End Sub

All the best

Here we have to discuss about how to write a text on image

this is the code written in Button_Click Event

Dim i As System.Drawing.Image = System.Drawing.Image.FromFile(Server.MapPath("~/Availability/2_type_A.JPG"))
Dim b As Drawing.Bitmap
b = Sold(i, i.Width, i.Height, "Sold", 100)
b.Save(Server.MapPath("~/Updated/2_type_A.JPG"), System.Drawing.Imaging.ImageFormat.Jpeg)

 Private Function Sold(ByVal resim As System.Drawing.Image, ByVal genislik As Integer, ByVal yukseklik As Integer, ByVal yazilacak As String, ByVal font As Single) As Bitmap
Dim resmim As New Bitmap(resim, genislik, yukseklik)
Dim graf As System.Drawing.Graphics = System.Drawing.Graphics.FromImage(resmim)
Dim firca As System.Drawing.SolidBrush = New SolidBrush(System.Drawing.Color.Red)
Dim fnt As System.Drawing.Font = New Font("Verdana", font)
Dim size As System.Drawing.SizeF = New SizeF(400, 400) ' this is the size of the font ie: width and height
Dim coor As System.Drawing.PointF = New PointF(XTextBox.Text, YTextBox.Text) ' this is X and Y Co-ordinates where you going to write the text on image
Dim kutu As System.Drawing.RectangleF = New RectangleF(coor, size)
Dim sf As New StringFormat()
sf.FormatFlags = StringFormatFlags.NoWrap
graf.DrawString(yazilacak, fnt, firca, kutu, sf)
Return resmim
End Function